The video was made for this article:

http://www.disneyanimation.com/technology/innovations/hyperi...

If you want to learn more about rendering then here is some more info:

Stanford CS348b course notes:

http://candela.stanford.edu/cs348b/doku.php

Cornell CS6630 course notes:

http://www.cs.cornell.edu/Courses/cs6630/2012sp/schedule.stm

Eric Veach's Phd thesis:

http://graphics.stanford.edu/papers/veach_thesis/

Physically Based Rendering: From Theory to Implementation by Matt Pharr, Greg Humphreys and Wenzel Jakob (book and open source implementation of a state of the art renderer):

http://pbrt.org/

Though they don't use the batching method outlined in the video - it would be interesting to see PBRT modified to do it and compare the resulting efficiency in rendering.

https://github.com/mmp/pbrt-v3/